Figure 8-8. - Diagonal brace angles
windows, as these procedures will vary with available building options.
Sheeting, both sidewall and roof, must always be started at the end of the building toward which the prevailing winds blow. This action will ensure that the exterior joint in the side laps is away from the blowing of the prevailing winds. When installing roof sheeting, always use a generous amount of mastic on the upper side of all roof sheets just before moving them to the roof. Turn the sheet over and put a bead of mastic on the lip of one side of the corrugation and along one end (near the end but never more than one 1 inch from the end). Be sure to apply a horizontal bead of mastic between aIl sheets in the end laps, BELOW THE LAP HOLES. The roof sheets must be dry when mastic is applied. Mastic is extremely important, and care should be exercised whenever applying it to ensure a watertight seal. Apply generous beads, especially at the comers of the sheets. Finally, the ridge cap will be installed ensuring proper watershed. As previous] y stated, the information in this manual is general information common to pre-engineered buildings.
The pre-engineered building can be insulated by any of several methods. A blanket type of insulation, in 2-foot-wide strips, to match the width of the roof and wall sheets can be installed between the sheets and structural at the same time the sheeting is installed. Or, a hardboard insulation can be applied directly to the inside surface of the structural, attaching it by helix nails or by sheet-metaI screws in holes prepared by drilling of the structural. Or, a wood framing can be prepared, attached to the structural, and a hardboard insulation is nailed to the wood.
Pre-engineered buildings can easily be set upside by side to increase the working area under one roof. When this is done, the adjacent rigid frames should be bolted back to back with a channel spacer at each girt location (fig. 8-9).
The cave struts are moved up the roof beam to the second set of 11/16-inch-diameter holes to provide a gutter. This arrangement provides a space between cave struts of 13 1/2 inches. A field-fabricated gutter can be installed.
Flat, unpainted galvanized steel of 24-to 26-gauge material should be used for the gutter. A depth of 6 1/4 inches is desirable with the downspouts located as required. Gutter ends should be lapped at least 6 inches and should be braze-welded for watertightness. Note that wall sheets can be used to form a gutter if the outside corrugations are flattened and all of the end laps are braze-welded.
Roof sheets must be cut shorter where they overhang the gutter. The corrugations can be closed with the continuous rubber closure with mastic applied to the top and bottom surfaces of the closure. An alternate method is to flatten the corrugations at the gutter and seal them with a glass fabric stripping set in plastic.Continue Reading